A headlight lens of this type is known e.g. from DE 10 2004 053 303 A1, DE 299 12 504 U1, DE 36 02 262 C2, DE 44 44 314 A1, FR 2 770 617 A1 and DE 34 30 179 C2. Headlight lenses for a motor vehicle headlight are additionally known from WO 03/074251 A1 and DE 100 52 653 A1.
DE 100 48 494 A1 discloses a headlight comprising an elongated light source, a light channel for the light source with an entrance surface and an exit surface, the light channel being formed by a plurality of light-transmissive laminae lying one above another at least in one direction, and the elongated light source forming an imaging on the entrance surface of the light channel, and also comprising a light-refracting element for projecting a light bundle, the exit surface of the light channel forwarding main and secondary light, the light-refracting element comprising a base part, on which substantially the main light impinges, while the secondary light substantially impinges on a second part of the light-refracting element, and the second part of the light-refracting element having different optical properties from the base part.
It is an object of the invention to reduce the weight of a headlight lens for a vehicle headlight, the intention being to ensure the desired optical properties. In this case the intention, in particular, is to comply with a permissible interval G* of a dimension—also referred to as gradient—for the transition (bright-dark boundary) from a region that can be illuminated by means of the vehicle headlight to a region that cannot be illuminated by means of the vehicle headlight, and a permissible interval HV* of a (so-called) HV value (also called dazzle value).